Windows 7 installed memory on a HP DC7900 (241 Views)
Posts: 19
Registered: ‎03-31-2009
Message 1 of 2 (241 Views)
Accepted Solution

Windows 7 installed memory on a HP DC7900

I installed Windows 7 on a DC7900 Convertible Minitower with 4 GB RAM. Why in Sysem Properties it is reported that installed memory is 4 GB but the usable memory is ony 3.5 GB?

(Please note that with Vista there are correctly reported and used 4 GB)
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Posts: 1,486
Registered: ‎08-17-2006
Message 2 of 2 (241 Views)

Re: Windows 7 installed memory on a HP DC7900

You are installing the 32 bit versions of Vista and Windows 7. No 32 bit OS can access more than about 3 1/2 GB of RAM. Vista had a change in SP 1 that made it report the amount of physically installed RAM (in your case, 4GB), but your system *STILL* could not access more than about 3 1/2 GB. Vista reports the amount of system accessible RAM.

If you want to access all 4GB of RAM, you'll have to install a 64 bit OS. You should also be aware that the performance gain between 3 1/2 GB and 4 GB of RAM is practically impossible to notice at all. To make any difference, you'll need not only a 64 bit OS, but at least 6GB of RAM *AND* programs that are written to access that much RAM.

The difference in multitasking between 3 1/2 GB of RAM and 4 GB of RAM will be negligible.

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